Pantograph



I Mar..3. 192's. 1,528,079

W. SCHAAKE' PANTOGHAPH Filed April 25, 1924 2 Sheets-Sheet 1 a /a INVENTDR ygvgmzsszz I y m Saboa/fe.

Patented Mar. 3, 1925.

* UNITED STATES PATENT OFFICE.

WILLIAM SCHAAKE, OFPITTSBURGH, PENNSYLVANIA, AS SIGNOR T WESTINGHOUSE ELECTRIG & MANUFACTURING COMPANY, A CORPORATION OF PENNSYLVANIA.

fANTOGRAIH.

Application filed April 25, 1924. Serial No. 708,895.

' tures for electric railway vehicles and more particularly to the operating mechanism for raising and lowering the current-collector shoes that are carried by the pantograph structure.

It is among the objects of my invention provide a pantograph structure in which the main actuating mechanism for raising the pantograph frame is supplemented by an auxiliary actuating means that functions to initially raise the pantograph frame.

It is a further object o-f'my invention to provide an auxiliary device for operating the anto-graph which shall also function as f a buffer when the pantograph i lowered to an inoperative position. It is a still further object of my invention to provide a pantograph structure and actuating means therefor which shall be of simple, compact and durable mechanical construction vand which shall function efficiently in its operation to provide; a quick-acting starting device for extending the pantograph frame.

Pantograph supports for current-collector shoes are constructed to facilitate raising or lowering the shoes relative to the overhead line structure, and the main actuating means utilized for the operation of the pantograph may be of any suitable type which 40. most readily adapts itself to the control of the operator.

It has been well established in practice that fluid-pressure control and actuating means is best adapted for pantograph operation. However, by reasonof the nature of the pantograph,there is an unavoidable dead center position, which is detrimental to efficient operation because of sluggishnessand slow response when it is desired to extend the pantograph. It sometimes happens that the pantograph drops below the dead center position, in which case it is necessary to climb upon the vehicle and raise 'the pantorotation of the other member.

graph'upbeyond the dead center position before it can be extended.

My present invention is directed to a fluid-pressure system which is adapted to be utilized in conjunction with an auxiliary fluid-pressure actuating mechanism that will obviate the difiiculties heretofore encountered, relative to the dead center position of the pantograph, and further provide a quick starting means for initiating the movement of the ,panto-graph before the primary extension means is actuated. This mechanism also functions as a buffer for the pantograph when lowered, thus eliminating possible damage to the operating parts.

-' In the accompanying drawings constituting a part hereof and in which like reference characters designate like parts:

Figure 1 is a plan view of a pantograph structure embodying the principles of my invention,

Fig. 2 is an end elevational view thereof,

Fig. 3 is a View, partially in side elevation and partially in cross-section, of the actuating means therefor,

Fig.4 is a diagrammatic view thereof showing the fluid-pressure system,

Fig. 5 is a similar view illustrating the arrangementand co-ordination of the several co-operating parts, and Fig. 6 1s a view in cross-section of a diaphragm utilized in the fluid-pressure system.

Referring to Fig. 1, the device therein illustrated comprises a supporting structure embodying a plurality of parallel L-shaped or angle members 1, which are secured together by. transverse supporting members 2 and 3, the end members 2 being mounted on suitable insulators 4 on the roof 5 of a railway vehicle. A pair, of shafts 6 are disposed transversely of the structural mem-' bers 1 and are-rotatably secured thereto bybearings 7. The ends of the shafts 6 are provided with cranks 8, which are interconnected by crossed links 9 so that the rotation of one shaft member will produce an equal A' pantograph structure 10 is secured to the shafts 6 and to a pair of current-collector shoes 11 which are connected by reinforcing strips .or castings 12 that are secured to the upper the shafts 6 and is provided with cranks 14, which are disposed in the. slotted openings 15 of a pair of cylinders 16. The cylinders are provided with pistons 17 that are adapted to engage the cranks 14:. The crank shaft 13 is connected to the shafts 6 so that when the former is rotated, the shafts 6 will be actuated and thereby effect an extension of the pantograph structure 10.

The cylinders 16 are connected to afluid pressure system as shown in Figs. 4 and 5, which comprises a pipe line 18 leading 'toa suitable source of flu-id pressure having a connection 19 with the cylinders 16. One of the cylinders is connected to a pipe line 20 leading to a pair of vertical buffer cylinders 21 by a pipe connection 22, Fig. 5. The cylinders 21 are provided with pistons 24 which are disposed underneath the castings 12 connecting the upper frame portions of the pantograph.

An air reservoir 25 is also connected to the pipe line 20, and a standard union 26 with a diaphragm having a relatively small opening is provided in the joint of the T 27 of the pipe line 20 and the connecting pipe 22 of the cylinder 16.

The operation of my device is briefly as follows: After the air or other fluid pressure is permitted to flow in the supply pipe 18, it will pass to the cylinders 16 through the connecting pipes 19 and also through the constricted opening of the diaphragm in the union 26 into the buffer cylinders 21 and the reservoir 25. The pantograph, being always sluggish in its collapsed position, is given a. quick starting action or impulse by means of the auxiliary pistons 24, which impulse is augmented by the pressure exerted on the cranks 14:, Fig. 3, by the pistons 17 of the air cylinders 16, thus raising the pantograph from a collapsed to an extended position.

If it is desired to lower the pantograph, the air or other fluid pressure, is'exhausted from the pipe line 18 and the cylinders 16, but the escape of air from the pipe line 20 leading to the buffer cylinders 21 is retarded by the diaphragm 30 in the union 26. The residual air in the buffer cylinders 21 and the reservoirs 25 ofiers an excellent buffer effect to the dropping pantograph, permitting it to rebound and drop to its collapsed position without exerting any detrimental shock or impact on the mechanism and its support.

It is evident from the foregoing descripion of my invention that the means for operating the pantograph provides a quickraising action and an adequate buffer effect for the pantograph structure, which is highly desirable in the efficient operation of such a current-collector device and which greatly enhances its serviceability.

Although I'have described a specific embodiment of my invention, it will be obvious to those skilled in the art that various modificationsi may be made in the details of construction and the design and proportion of the several co -operating parts without departing from the principles herein set forth.

I claim as my invention 1. In a pantograph trolley structure, the combination with a primary actuating mechanism, of an auxiliary device adapted to initiate the movement of the pantograph frame.

2. In a pantograph trolley-structure, the combination with an operating-mechanism for actuating the pantograph frame, of means for etfectingn quick-raising action.

3. In a pantograph trolley structure, the combination with anoperating mechanism for actuating the pantograph frame, of means for effecting a quick-raising action,

said means comprising afluidepressure'system.

4. In a pantograph trolley structure, the

combination with an operating mechanism for actuating the pantograph frame, of means for effecting a quick-raising action and a resilient retardingaction.

5. In a pantograph trolley structure, the combination with an operating mechanism for actuating the pantograph vframe, of means for effecting a quick-raising :action and a buffer action.

6. In a pantograph trolley structure, thecombination with an operating.mechanism for actuating the pantograph frame, of means for effecting a quick-raising action and a bufi'er action comprising a fluid-pressure system including areservoir and a pair of piston members.

7 In a pantograph trolley structure, the combination with an operating mechanism for actuating the pantograph frame, of

means for efiecting a quick-raising action and a buffer action comprising a flui d pressure system including a reservoir, and-a pair of piston membersand means for retarding the vpressure ofsaid system.

8. In a pantograph trolley structure, the combination with a fluid-pressure operating mechanism for actuating the pantograph frame, of a plurality of piston members and means forrestricting the flow of pressure between said operating mechanism and said pistons.

9. In a .pantograph trolley structure, the combination with a fluid-pressureoperating mechanism for actuating the pantograph frame, ofa reservoir and a plurality ofypiston members and a diaphragm for restricting the flow of pressure between said'operatingmechanism andsaid reservoir and pistons.

10. In a pantograph trolley structure, the combination with an operating mechanism for raising the pantograph frame, of means for initiating movement of said structure.

11. In a pantograph trolley structure, the ally engage the collector shoes, and means combination with a pantograph frame haV- for restricting the flow of pressure between 10 ing collector shoes mounted thereon, of a some of said cylinders and said reservoir. fiuidpressin-e operating mechanism therefor In testimony WhereofI have hereunto subcomprising a plurality of fluid-pressure scribed my name this 17th day of April operable pistons and cylinders therefor, and 1924. a reservoir connected to said cylinders, certain of said pistons being adapted to initi- WILLIAM SCI-IAAKE. 

